Reflector device



Sept. 16, 1941.- Y' J. c. HAGGART. JR 2,255,748

REFLECTOR DEVICE Filed Jan. 5, 1940 INVENTOR Jaw 6. H/raaw /k.

KIA/v04- ATTORNEY Patented Sept. 16, 1941 REFLECTOR DEVICE John 0.Haggart, Jr., Westfield, N. J., assignor to Signal Service Corporation,a corporation of Delaware Application January 5, 1940, Serial No.312,486

3 Claims.

This invention relates to holders for autocollimating devicesparticularly central triple reflectors in the form of discs such as areused, for example, in signs or on standards along the sides of highways.

For the purpose of mounting such reflecting discs on a metal plate, itis usual to provide a metal cup-like holder for them which has itsflange turned in and overlapping the edge of the disc.

These disc reflectors most commonly are made of a plastic material whichis more easily subject to deformation than is glass. At any rate intheir usual form the reflective disc portion is surrounded by a rearwardperipheral axial flange, and the assembling of these reflectors in theirmetal holders has been a source of trouble for the reason that thedrawing of the sheet metal around the flange in peripheral clampingrelation with the front face has been apt to warp the disc and impairits optical properties.

The primary object of the present invention is to provide a holderconstruction which will in its application to the disc avoid theproduction of Warping stresses.

Another object is to facilitate the proper initial relative positioningof the disc in the holder in its blank form.

Other objects are ease of assembly and simplicity and cheapness ofconstruction. Still other general objects will appear from the followingdescription.

In accordance with this invention the holder is designed so as to avoidradial stresses on the flange. Its center is preferably raised so as tofit within the flange and thus locate the re-- flector, and the diameterof the cup blank which is the initial form of the holder at thebeginning of the assembling operation considerably exceeds that of thereflector. The top edge of the cup flange is turned in to form anoverhanging lip, and the flange is turned back upon the bottom of theholder, thus bringing the lip down upon a circumferential shoulder onthe front face of the disc and producing an axial pressure. To assurethat there is no radial component to the stress the holder flange in itsfinal form is spaced from the periphery of the disc.

The illustrated embodiment of the invention will now be described afterwhich the invention will be pointed out in the claims.

Figs. 1, 2 and 3 are sectional elevations showing an initial,intermediate and final condition, respectively, of the assembled partsin the formation of the unit.

Fig. 4 is a plan, partially in section on the line 4-4 of Fig. 3, of thecompleted unit.

The holder in its initial blank form is a cup shape sheet metal memberhaving its center la raised and its edge 2 turned up in the form of acylindrical flange. The reflector 3 is meniscus in shape with thecentral triple, trihedral reflecting formations on its back or concaveface and surrounded by a peripheral axial flange 3a the front face ofwhich is shouldered, as indicated at 31). The reflector is disposed inthe holder with the rear face of the flange 3a opposing the flat,annular bottom portion lb of the holder and surrounding the raisedcenter la of the holder. An annular gasket 4 is interposed between theface of the holder and the flange 3a, this gasket in the form shownhaving an upturned inner edge forming an annular cushion between theinner axial face of the flange 3a and the annular shoulder connectingthe portions la, and lb of the bottom of the holder. This constructionserves to center the reflector in the holder.

As shown in Fig. 1 of the drawing, the diameter of the holdersubstantially exceeds that of the reflector, the flange 2 being spacedfrom the outer periphery of the flange 3a when the reflector is on itsseat coaxial with the holder. Therefore, the flange 2 can be closed downupon the shoulder 31) without exerting any radial stress upon the flange3a of the reflector.

In practice this is accomplished by folding the flange 2 at its bottominwardly upon the adjoining bottom portion lb, as indicated at 5, andeither at the same time or previously forming an inturned lip 6 at theouter edge of the flange 2. This lip may be partially formed, as shownin Fig. 2, before the reflector is inserted, but with a proper tool theformation of the lip is completed and the fold 5 is formed, eithersuccessively or simultaneously.

It will be apparent that the axial resilient pressure of the lip 6 onthe shoulder 31) is effected without the production of any warping forceupon the reflector, as would be the case if the flange 2 were drawntightly around the edge of the reflector. Being spaced from thereflector periphery the flange can be turned in to form the fold 5 andthus draw the lip 6 down on the shoulder with the necessary resilientforce.

The assembled units are inserted in proper sized holes in the sign orstandard 7, a back plate (not shown) or other suitable means beingemployed to hold them in place. The fold 5 forms disc shape and havingan axial peripheral flange v p with a peripheral shoulder on its frontface, and- I a sheet metal holder bearing against the rear face of theflange having a central raised portion fitting within the flange andhaving a peripheral forwardly extending flange spaced radially from thereflector flange with its forward jedge bent inwardly and bearingresiliently on said shoulder.

2; A combined reflector and holder therefor comprising a central triplereflector of generally disc shape and having an axial peripheral flangewith a peripheral shoulder on its front face, and

a sheet metal holder bearing against the rear face of the flange havinga central raised portion fittingwithin the flange and having aperipheral forwardly extending flange spaced radially from the reflectorflange with its forward edge bent inwardly in contact with said shoulderand the holder flange at its junctureiwith the back portion of theholder being permanently bent back upon the holder and thereby effectinga resilient engagement of the holder flange with'the shoulder.

3. A combined reflector and holder therefor comprising a central triplereflector of generally disc shape and having an axial peripheral flangewith a peripheral shoulder on its front face, a sheet metal holderbearing against the rear face of the flange having a central raisedportion fltting within the flange and having a peripheral forwardlyextending flange spaced radially from the reflector flange with itsforward edge bent inwardly in contact with said shoulder and the holderflange at its juncture with the back portion of the'holder beingpermanently bent back upon the holder and thereby effecting a resilientengagement of the holder flange with the shoul

